Pump for refrigerating apparatus



. FRANK R. wnsr, or DETROIT,- MICHIGAN,

A CORPORATION or MICHIGAN Patented July 8, 1930 PATENT OFFICE ASSIGNOR 'ro COPELAND-PRODUCTS, mos;

PUMP FOR REFRIGERATING APPARATUS Application filed June 23,

- This invention relates to refrigerating apparatus. It has to do particularly with a novel and extremely compact compressor mechanism, and a novel method and apparatus for supplying motive power to the compressor together 'Wlth a novel manner of conducting the refrigerant to and from the compressor structure.

In the mechanical refrigeration art, it has been the general practice to utilize a compressqr, as a unit in a refrigerating system, and such compressors, While more or less efficient during the first few months of operation, have presented important difliculties after continued service. Such difficulties have been due mainly to the-necessity ofia rotating seal to prevent the escape of refrigerant from the compressor housing. It

has been the usual practice to utilize -ap-'.

proximately an 80 pound spring to keep the stationary seal and shoulder on the crank shaft in sealing contact, and due to this spring, it has heretofore been necessary to limit the speed of the compressor to approximately 325-.to 400 R. P. M. in order to reduce the wear between such parts. Furthermore, the compressors of the prior arthave been provided with thrust bearings, connecting rod bearings, and other parts which'of necessity have required accurate-and expensive machining. v

It is the object of the present invention to completely eliminate the rotating seal or joint of the prior art and to replace the same with a non-rotative flexible sealing member which will last the life of the compressorand permit any speed desired. More specifically, the present invention contemplates the supplying of motive force to the reciprocable piston or pistons by means'of an oscillating memher, the entrance of which into the cylinder housing, or crank case housing, is sealed by means of a non-rotative and permanently fixed bellows or flexible sealing member. With this construction, there is no rotating bearing in the compressor itself and practically no parts which will cause nocks due to wear. The bearings in the compressor housing are merely oscillating pivot bearings, requirlng no particular accuracy in 1928. Serial No. 287,852.

manufacture or assembly, and which will be very quiet in operation over a long period of time.

A further feature of the present inven tion resides in the design and'compact arrangement of parts whereby the power transmitting means and the compressor form a unitary structure so constructed as to eliminate belts, fly wheels, motor pulleys, etc. In combination with this compact assembly, the present invention contemplates the use of ported intakes, together with an increased compressor speed. "This'novel manner of operation not only permits less starting effort and the use of an electric motor having a minimum starting torque, but also greatly increases the efliciency of the compressor at high speeds.

' Various other features will be brought out in the specification and claims. r

In the drawings Fig. l is a vertical sectional view taken mainly" on line 15-1 of Fig. 2. v

Fig. 2 is an end elevation, partly in sec- .tion, taken on line 2-2 of Fig. 1.

Fig. 3 is a plan View, partly diagrammatic and partly in section, and showing in particular the preferred relationof the novel compressor unit with the remainder of the refrigerating system.

Fig.4 is an enlarged fragmentary detail view, showing the manner of connecting the operating lever to the cylinder structure.

Fig. 5 is a fragmentary sectional view taken on line 5-5 of Fig. 4. a

The structure embodied in the present invention is quite radical from standard compressor design, and while similar terms may be used in some instances in describing the design and arrangement of the parts thereof, it will be understood that such terms apply specifically to the present rather than to the generally accepted parts of standard compressor design.

The present invention is particularly adapted to twoscylinder compressor design, inasmuch'as two cylinderscan be utilized for very little'addit'ion-in expense. In Fig. i l I'have shown a two-cylinder compressor structure, comprising the two horizontally construction I ,meaeve I positioned cylinders 1 and 2. These cylin the pistons 3 and 4 and the integral connectd a suitable pin 7. The upper end of the operating arm 6 is preferably bifurcated and constitutes a cross head for a sliding shoe block element 8. It will be obvious that as the 7 arm 6 slides back and forth that the pistons 3 and will be horizontally reciprocated and that there will be a very slight sliding action between the block 8 and the upper end of the arm 6', whereby the pin 7'1nerely acts as a pivot pin and does not absorb any severe im The is preferably integrally-connecte to a p'ower arm or lever 9, and this unit comprislng the operat ng lever 6'and the power lever 9 is preferably pivoted A as at 10 and 11. The upper end of the lever v as Wise

9 is slidably connected as at 12 with a strap member 13 which forms a part of an eccentrio mounting for the end of the motor shaft I 14, the motor bein generally designated 15.

It will thus be viou'sthat I preferablyutilize a direct drive and that. oscillating mfovement is imparted to the power arm 9 by reason of the eccentricstrapunit 13. p a The compressor or cylinder housing may c be generally designated 16 and suchhousing comprises the cylinders 1 and 2, the gas receivlng chamber 17 and the downwardly extending chamber 18. Sec-ured to the lower end of this chamber 18 is an annular'ring 19 adaptedto positively seal or position the inner end of a bellows member 20. In other words, the inner annular end of the bellows 20 is securely held in place by the annular ring 19 whereb to present a positive nonrotating seal. The operating lever 6 terminates in an enlarged or up-set end 21'wh1ch forms an annular flange for receiving the other end of the bellows'20, such other end of the bellows 20 being positively held in sealing position by means ofv a second annular'ring 22, which is securely bolted to the T e bel1ows 20 is preferably so positioned,

.jxo'rfin other words, the. bottom of the chamber h 55.

18'and the flange 21 of the lever 6 are so po- .sitioned, that the opposite ends of the bellowsinember are equally distant from the 'center 'lineof the pivots 10 and 11. It will thus be obvious that although the bellows 20 issubjected to very little flexing during operation .of the compressor, that the fl 'ng that does takeplacewill be localized a the central part thereof, whereby to insure 'ermanence of the bellows member. The exing of the bellows, is further reduced to a- ,31, such ports minimum by reducing the distance of travel of the pistons, which is primarily due to the. increased R. P. M.as will'be later explained.

- The housing for the power arm 9-as well as the lower end of the operating arm 6 is preferably formed integrally with the compressor housing 16. compact and inexpensive casting-and such housing need not be accurately machined'as it only contains three pivots 10, 11, and 14, which are merely oscillating pivots. Very little oil is required in a compressor of the presentdesign, and the entire compartment "Ill This produces af 'very 18 may be filled with oil up to a point where" I it may be utilized as a lubricantfor the pis-- tons-3 and 4.

.Due tothe non-rotative flexible sealing oint it is possible to increase the speed or" the compressor to approximately 900 R. P.

M., although motors having a-standard R. P. M. of 1700 to 1800 R. P. M. can be used, and in this event the compression space inthe cylinders is preferably 're'duced.

In direct'combination with this increased speed, I preferably introduce the refrigen ant intothe compressor at the point. 17

and this refrigerant is alternately fed into {eachcylinder by meansof the ports 30 and eing uncovered *by the v end of the piston at'one end of the stroke. Separate intakes could be provided in; each cylinder wall'for each piston, and thus eliminate the passing of the refrigerant above any body of oil. It will also be obvious that intake valves similar to the discharge valves shown could be installed .in the heads of the pistons, as in standard practice. However, I

prefer to use the ports as this offers a mate- Y rial advantage in that less starting elfort has to be exerted by the powermeans, when brmging the compressor up'to speed. This is due to poor volumetric 'eiiiciency until maximum piston speed has been attained, as

at low speeds there willbe considerable gas flow losses through the ports. If the compressor were operated at a low R. P. 'M. it is obvious that a certain percentage of trapped gas would be allowed. to escape back, thus leaving only a partial amount of gas to be compressed, requiring less power than'when' up to speed.

When the compressor has increased to full speed, say approximatelv 900' R. P. M. the igher piston speed and gas velocity will glve'the in-going gas a positive inertia which prevents its backing up before the piston."

shuts off the port. It will be" obvious that this use of ported intakes permits the use of an electric motor having a minimum" starting torque. This increase in R. P. M.

greatly increases the elficiency of the compressor and thus greatly increasesthe refrigerating ef-' feet so that the period of operation of the compressorwill be greatly decreased.

In Fig. l'Ihave shown the .ends of the cylinders 1 and 2 as being provided with suitable exhaust valves and exhaust valve housings 32 and 33, and the compressed gasmay be conducted away by means of suitable conduits 34 and 35. vIn the partly diagrammatic showing in Fig, 3 the exhaust conduits fromthe compressor housing are shown as oiningat the front'of such housing as at 36 from where all the compressed gas is conducted to the condenser in the usual manner.

. Not only is the flexing of the bellows ma- 'terially reduced by increasing the R. P. M.

and shortening the stroke of the piston, but

suchflexing is also materially reduced by increasing the lengthof the power arm. This long power arm also reduces side wear ofthe piston'and cylinders. It will be obvious that other modes of power transmission between the motor and the operating lever 6 maybe utilized but for extreme compactness, simplicity, and ease in-assembly, the present showing is the preferred one.

It will be understood that the crank housing may be provided with suitable cover plates at the ends of the stub shafts 10 and 11,

.whereby. the housing may be filled with oil up to a point adjacent the shaft 14;.

What I claim is: i

1. A unit for a refrigerating system, comprising a reciprocable p1ston,a housing therefor, a member connected to said piston and extending throughsaid housing at an angle approximately a right angle tosaid piston,

and a flexible sealing means positloned around said member and the opening in the housing and being positively secured at one end to said housing and at the other end'to the end of said member, saidimember being pivotally mounted at points external of said flexible sealing member and the axis of said pivotal mounting passing substantially through the center of said sealing member.

2. A unit for refrigerating systems, comprising a cylinder housing, a piston mounted therein for reciprocation, an oscillatable operating arm-connected to said piston and extending through said I housing, a non-rotatable flexible seal connected to an end of said arm andsaid housing for sealing the housing, a power arm integrally connected to said operating arm and extending parallel thereto and in the same direction from the axis of oscillation of said operating arm, a rotatable operating means connected with said power arm in such a manner as to cause oscillation thereof, the oscillation ofsaid power arm in turn causing oscillation of said operating arm and reciprocation of said piston, the movement of said operating arm being absorbed by. the flexibility of. said seal, and said flexlblei seal being so positioned between said arm and said housing that the flexing :thereof will take place about an axis intermediate the ends. v

3. unit for refrigerating systems,com-

prising a cylinder housing, a piston reciprocable therein, a member. for reciprocating said piston and extending through said housing, a non-rotatable sealing member connected with said housing and said actuating member, and power means .for actuating said member adapted to be operated at a relatively great speed and a port in the wall of said cylinder controlled by said piston for admitting the fluid to be .compressed.

4. A unit for refrigerating systems, comprising a double cylinder housing with opposed cylinders, integrally connected pistons for said cylinders, an oscillatable operating member pivotally connected to said pistons in such a manner as to permit positive longi: tudinal -movemcnt of the pistons and said piyot point, saidmember extending through sald cylinder houslng, anon-rotatable flexible sealing member connectedto one end of said member and sald hou'smg, and means externally thereof for oscillating said member to cause reciprocation of said piston, said oscil-' lation'being. about an axis passing through and intermediate the ends of said sealing member.

5. A unit for a refrigerating system, comprising a cylinder housing'contalning a reciprocable piston, a member pivotally mounted at one end at a point remote from the piston and extending through said housing for reciprocating the piston, and a flexible cylindrical sealing member connected at one end to said housing and at the other end to said piv-, oted end of said member, said sealing member being so positioned that the axis of said pivotal mounting will be centrally of and equidistant from the ends of said sealing member.

6. A unit for a refrigerating system,'comprising a compressor housing having a' reciprocable piston therein, and including a chamber extending at right angles to said plston, a second chamber extending laterally from the outer .end of the first chamber, an arm said rst chamber and connected at one end ivoted at one end extending through to said piston for reciprocatingthe same,

for, a member pivotally mounted at one end and connected at its opposite end to said piston and extending through said housing at an angle approximately at right angles to said piston, and a flexible sealing means positioned around the first mentioned end of said member and the opening in the housing and being positively-secured at one end to said housing and at the other end to the end of said member, the axis of movement of said member being intermediate the ends ofsaid sealin' means.'

8. unit for a refrigerating system, com- .prising a reciprocable piston, an oscillatable member connected to and extending at an angle approximately at right angles to said "pistoma'housing for said unit including a cylinder housing,achamber extending at substantiallyrightangles to said cylinderhous ing and'enc osing said member, and an additional chamber extending transversely at the end of said first chamber all formed as an integral unit, means'positioned in said second chamber for causing oscillation of said member, and a bellows member connected at one end to one end of said oscillatable member and at the other end to the housing at the joint between said first chamber and said second chamber. v

9. A unit for a refrigerating system, comprising a reeiprocable piston, an os'cillatable member connected to and extending at an angle approximately at right angles to said piston, a housing for said unitincluding a cylinder housing, a chamber extending at substantially right angles to said cylinder i housing and enclosing said member, and an additipnal chamber extending transversely at the end of said first chamber all formed as, an integral unit, means positioned in said second chamber for causing oscillationiof said member, and a bellows member connected at one end to one end of said oscillatable member i and at the otherend'to the housing at the joint betweensaid first-- chamber and said; second chamber, thdmeans 'in said second chamber for causing oscillation of said memher being pivoted about an axis extending substantially through the central part of said.

bellows member.

In testimony where'ofI aflix my signature.

FRANK R. WEST, 

